A light emitting element having a layer including a light emitting substance between a pair of electrodes is used as a pixel, a light source or the like, and provided in a light emitting device such as a display device and a lighting device. In such light emitting devices, the reliability of a light emitting element is closely related to the capability of a light emitting device. For example, in a case where short-circuiting is generated between electrodes of a light emitting element, display image is distorted or a sufficient amount of light cannot be emitted.
Therefore, development of a light emitting element which has few defective elements and can emit stably for a long period has recently advanced. For example, in Patent Document 1, a technique of manufacturing a light emitting element which works at a low driving voltage by using a metal oxide whose work function is high, such as molybdenum oxide, as an anode, is disclosed. In addition, an effect of extending its life time is obtained.
[Patent Document 1] Japanese Patent Publication No. Hei 9-63771
It is an object of the present invention to provide a light emitting element which can reduce a defective operation due to crystallization of a compound.